England co-captain Dylan Hartley has linked up with the rest of the squad, boosting hopes he will play some part in the Six Nations.

Hartley was left out of Eddie Jones' initial squad, with a knee injury keeping him out of the opener against Ireland as England enjoyed a superb 32-20 win in Dublin.

But the hooker has now joined his team-mates as they prepare to face France at Twickenham this weekend, and defence coach John Mitchell is keen to see Hartley back in action.

"It's good to see Dylan - he looks in great shape," Mitchell told Sky Sports. "He is an excellent advertisement for a lot of the guys.

"He's been our captain and a leader, and for him to come in, in the shape that he's in, is a credit to him. It's a great reference to others in the group because, ultimately, that's what we want. That's exciting, especially when a player at the camp is in good nick.

"It's been good to see him, good to chat with him, have an update.

"Ultimately, he gets two extra days a week in the programme so I think we should hope to see him feature at some point in the Six Nations."

Billy Vunipola says the absence of Dylan Hartley through injury will be a "massive" loss to England but has backed Saracens colleague Owen Farrell to thrive as the team's sole captain.

Farrell was promoted to co-captain alongside Hartley during the November internationals, having filled in for the Northampton Saints man on the June tour to South Africa.

It was confirmed by coach Eddie Jones on Thursday that Hartley will miss the start of the Six Nations with a knee injury, ruling him out of a Dublin showdown with defending champions Ireland, who completed the Grand Slam at Twickenham last year.

But some believe it is Farrell who will end up leading England into this year's Rugby World Cup in Japan and Vunipola says the 27-year-old has the character to fill the leadership void left by Hartley against Ireland.

"It'll be massive," Vunipola told Omnisport, speaking on behalf of Land Rover. "Dyl's been there from the start with Eddie and they run a tight ship but a fun ship.

"He's a great leader and we'll definitely miss him in and around camp. He's a great guy and a great captain as well, so we'll definitely miss him.

"But I think Faz [Farrell]... everyone knows the standards he sets and hopefully he can set them for us and lead by example."

Vunipola added that both men command the same amount of respect in the squad, commenting: "They're kind of the same body with two different heads. Everyone listens and everyone respects [what they say]."

The Saracens number eight said it was "lovely" to see his name in Jones' squad after injuries have limited his involvement in the past two championships to just two appearances in 2017.

He is joined in the squad by clubmate and fellow back-row forward Ben Earl, who - along with Ollie Thorley, Dan Robson and Jack Singleton - is one of four uncapped players to make the cut.

"For people that probably don't know Ben Earl, he's a lot like a small Michael Hooper," Vunipola explained.

"He's strong, he's powerful, he's compact, but he's fast. He's good over the ball and I'm just happy to have another Saracens team-mate in the team.

"It's testament to the system we have here.

"I know he'll do well in training, but we're all pushing for the same spot, so we just have to push each other as much as possible."

Billy Vunipola is a Land Rover ambassador. Land Rover shares and understands the values of rugby. @LandRoverRugby

Joe Cokanasiga retains his starting berth for England's Cook Cup clash with Australia, while Dylan Hartley and Manu Tuilagi have been named among the replacements.

Cokanasiga scored a debut try in the victory over Japan last weekend and will start on the right wing on Saturday, with Jonny May coming in on the left flank as Chris Ashton and Jack Nowell miss out due to injury.

Jamie George gets the nod over co-captain Hartley, who is set to make a record 56th international appearance at Twickenham off the bench.

George Ford drops out of the side with Owen Farrell restored at fly-half to take skipper duties and scrum-half Ben Youngs regains the number nine shirt.

Henry Slade and Ben Te'o reunite in midfield, with Tuilagi in contention to win his first cap for well over two years after recovering from a groin strain.

Sam Underhill starts at openside flanker, so Mark Wilson moves to number eight and Brad Shields comes in at blindside flanker with Nathan Hughes having to settle for a place on the bench after serving a ban.

Eddie Jones shifts Courtney Lawes into the second row alongside Maro Itoje, while props Ben Moon and Kyle Sinckler are restored to the side.

Joe Cokanasiga scored a debut try as England overcame an almighty scare to fight back and beat Japan 35-15 at Twickenham.

Eddie Jones challenged a much-changed team to "smash" his former side, but England were in danger of being humiliated when they trailed 15-10 at half-time on Saturday.

An enterprising Japan team were great value for their lead, Ryoto Nakamura and Michael Leitch scoring first-half tries, with England disjointed after Jones made 11 alterations to his starting line-up following the defeat to New Zealand.

Danny Care's early try had put England in front but they lacked cohesion in a poor first-half display before raising their game following the introduction of Owen Farrell at the interval.

Mark Wilson's first international try put them back in front, then Cokanasiga and Dylan Hartley went over as England finally clicked into gear with a clash against Australia to come next weekend.

George Ford, captain for his 50th cap, scored 12 points with the boot and Elliot Daly was on target with a long-range penalty in a first half which Japan dominated, but they were ultimately emphatically beaten.

England took just three minutes to take the lead with a blistering counter-attack, Daly, Cokanasiga and Jamie George combining down the left flank and Care darting away for an opening try after Yu Tamura failed to find touch.

Japan applied sustained pressure in a brilliant response, Tamura getting them on the board from the tee after they had opted against shots at goal in favour of set-pieces when scenting a try.

The Brave Blossoms were rampant and capitalised on their numerical advantage with George in the sin-bin for going off his feet after a careless pass from Care was intercepted.

Nakamura took a fine pass from Fumiaki Tanaka to burst through and go under the posts as England were caught out from a scrum and although Daly levelled with a long-range penalty, Japan were back in front with a second try just after the half-hour mark.

It was again a combination of inventive attacking and poor defending which gave the underdogs a half-time advantage, Leitch ploughing his way through Care and stepping past Daly all too easily before touching down after Chris Ashton was withdrawn due to injury.

Jones introduced Farrell at the break and Ford reduced the deficit to two points with his second penalty.

Japan were finally undone for a second time, Ford throwing a dummy and feeding the onrushing Wilson, who finished off a slick move just before the hour-mark after Care got rare quick ball.

Ford added the extras and was on target with another penalty before Richard Wigglesworth picked out Cokanasiga with an inviting pass, and the powerful young wing shrugged off a couple of tackles to score on his international bow.

Hartley dotted down when Japan failed to halt a driving maul to add gloss with Japan fading after causing England so many problems with a vibrant first-half display.

England were on the wrong end of a contentious late decision as they fell to a 16-15 defeat against New Zealand in a gripping Test at Twickenham on Saturday.

Owen Farrell got away with a controversial tackle on Andre Esterhuizen beyond the 80th minute in a 12-11 victory over South Africa last weekend, but Eddie Jones' side saw a marginal call go against them on this occasion as Sam Underhill's 75th-minute try was controversially chalked off by TMO Marius Jonker.

Courtney Lawes was adjudged offside when he charged down TJ Perenara's kick before Underhill, who started at openside flanker in place of the injured Tom Curry, beat Beauden Barrett to score in the corner.

England found themselves behind despite an electric start that saw Chris Ashton take less than two minutes to mark his first England start in over four years with a try and Dylan Hartley also cross to put the fired-up hosts 15-0 up.

Full-back Damian McKenzie finished a lovely move in the 39th minute to start the New Zealand comeback, before Barrett added the extras and finished the first half with a penalty.

A drop goal and another penalty from Barrett then put the All Blacks in front for the first time, and they held on after Underhill's late score was ruled out in debatable fashion.

Brodie Retallick failed to take in Farrell's kick-off and the hosts made the most of the early ball with Ben Youngs looping a brilliant pass that Ashton took into the corner to become the first England player to score more than two tries against the All Blacks.

Farrell's conversion attempt bounced back off the right-hand upright, but he slotted through a drop goal in the 10th minute to surpass 700 points in an England shirt.

England maintained the incessant pressure and Elliot Daly's excellent kick gained territory before Hartley touched down off an unstoppable driving maul from the line-out in the 24th minute.

New Zealand turned the tide towards the end of the first half and McKenzie dived beside the posts following a lovely offload from Barrett, who successfully kicked a penalty to reduce the deficit to five points at half-time.

Jamie George replaced co-captain Hartley for the second half and the All Blacks wiped out the hosts' lead through a drop goal from Barrett and a penalty following the Saracens hooker's stray line-out.

Retallick continued to disrupt George's line-outs but Underhill thought he had won it after a brilliant step to get beyond Barrett and touch down on the left, only for England's celebrations to be short-lived due to Lawes' infringement.